Some Channel tests.

S17-concurrency/channel.t

@@ -0,0 +1,34 @@
+use v6;
+use Test;
+
+plan 12;
+
+{
+    my $c = Channel.new;
+    $c.send(1);
+    $c.send(2);
+    is $c.peek, 1, "Peeked first value";
+    is $c.receive, 1, "Received first value";
+    is $c.poll, 2, "Polled for second value";
+    ok $c.peek === Nil, "peek returns Nil when no values available";
+    ok $c.poll === Nil, "poll returns Nil when no values available";
+}
+
+{
+    my $c = Channel.new;
+    $c.send(42);
+    $c.close();
+    nok $c.closed, "Channel not closed before value received";
+    is $c.receive, 42, "Received value";
+    ok $c.closed, "Channel closed after all values received";
+    dies_ok { $c.receive }, "Receiving from closed channel throws";
+}
+
+{
+    my $c = Channel.new;
+    $c.send(1);
+    $c.fail("oh noes");
+    is $c.receive, 1, "received first value";
+    dies_ok { $c.receive }, "error thrown on receive";
+    is $c.closed.cause.message, "oh noes", "failure reason conveyed";
+}